1. Field of the Invention
The present invention relates to firearms. More specifically, it relates to a firearm magazine. Even more specifically, it relates to a firearm magazine wherein the expanding gasses from the breech are used to advance the bullets in the magazine. Yet even more specifically, it relates to a gas actuated firearm magazine wherein a piston that includes a biasing portion serves as a follower. More generally, the present invention could be used in any application where compressed gasses are used to advance one object at time a specified distance, such as in various manufacturing processes.
Thus it can be seen that the potential fields of use for this invention are myriad and the particular preferred embodiment described herein is in no way meant to limit the use of the invention to the particular field chosen for exposition of the details of the invention.
A comprehensive listing of all the possible fields to which this invention may be applied is limited only by the imagination and is therefore not provided herein. Some of the more obvious applications are mentioned herein in the interest of providing a full and complete disclosure of the unique properties of this previously unknown general purpose article of manufacture. It is to be understood from the outset that the scope of this invention is not limited to these fields or to the specific examples of potential uses presented hereinafter.
2. DESCRIPTION OF THE PRIOR ART
Magazines for feeding ammunition into a firearm that utilize the expanding gasses from the previous cartridge's explosion to move the next into the firing chamber are known. Likewise, springs have been used to advance the cartridges in a magazine and to ensure their proper positioning and feeding into the firing chamber. Still, the occasional misfire or "jam" will occur. The present invention seeks to address this problem by providing a unique piston arrangement with a resilient member on the top thereof, to thus doubly assure the proper advancement of the cartridge. Extending from the sides of the piston portion of the device are a number of biased and cammed ratcheting pins that cooperate with apertures on the inner wall of the magazine assembly. Between the inner and outer wall of the magazine is a blow by rail to allow any excess gas to be vented. As will be seen, the simplicity and effectiveness of my invention is not rivaled in the prior art.
During a search at the U.S. Patent and Trademark Office, a number of related patents were uncovered that are discussed hereinbelow:
U.S. Pat. No. 2,569,995, issued to Lumir Vojtech Kapsa on Oct. 2, 1951, shows a spring fed magazine primarily for use in air guns. This device consists of a tube with a pushing member and a compression spring. This is dissimilar from the present invention in that no utilization of gas from an exploding cartridge is discussed.
U.S. Pat. No. 2,620,582, issued to Earl M. Stukas on Dec. 9, 1952, shows a firearm magazine wherein a compression spring impels a follower in the magazine to urge the bullets forward. On one side of the magazine is an elongated slot through which protrudes a button that is attached to the follower. On the opposite side of the magazine there is a rectangular opening, to allow for the loading of cartridges, that is secured by a removable cover plate. Thus, the follower can be retracted by the button and the magazine filled. By contrast, the device of the instant invention is impelled by the expanding gasses of a fired cartridge.
U.S. Pat. No. 2,828,568, issued to Edwin G. Sakewitz on Apr. 1, 1958, shows a cartridge indicating magazine for pistols. This device also uses a spring to impel the follower and includes a visual numerical indicator. By contrast, the device of the instant invention, as mentioned in the discussion of the Stukas patent above, utilizes the expanding gasses from the breech of the firearm.
U.S. Pat. No. 3,069,976, issued to Frederick F. Stevens on Dec. 25, 1962, shows a gas operated semi-automatic pistol wherein the residual gas pressure remaining in the barrel after firing moves a cam follower to relieve tension on a series of springs to both eject the empty cartridge and move the next bullet into the breech. This is dissimilar from the present invention in that no gas driven piston within the magazine directly in contact with the magazine follower is disclosed.
U.S. Pat. No. 4,343,107, issued to Benno Kaltenegger or Aug. 10, 1982, shows a cartridge magazine for pistols. This is another of the spring loaded magazine type and as such is dissimilar from the present invention, which uses the gas pressure from the breech to advance the succeeding cartridge.
Another patent of interest is U.S. Pat. No. 4,495,720 issued on Jan. 29, 1985 to Robert Bross. This discloses a handgun magazine with a pommel base. Unlike the present invention, there is no teaching of using the gasses from the breech of the gun to impel the cartridges in the magazine.
U.S. Pat. No. 4,563,937 issued to Bernard C. White on Jan. 14, 1986 discloses a gas actuated pistol wherein a vent proximate the muzzle of the barrel allows the compressed gasses to enter a chamber and drive a piston body, and thus a bolt carrier, rearwards to withdraw the bolt from the barrel assembly and likewise eject the casing. However, the cartridges in the magazine are urged towards the breech by a spring mechanism, thus differentiating this disclosure from the instant invention.
Next is U.S. Pat. No. 4,811,510 issued to M. Gaines Chestnut on Mar. 14, 1989. This discloses a cartridge magazine with means for increasing the number of rounds that it can hold. This is accomplished through use of a conforce spring in combination with leaf springs that also serve as legs on the follower body. As in a number of the patents discussed above, this is clearly dissimilar from the instant invention, as no use of the compressed gasses from the breech is disclosed.
In U.S. Pat. No. 5,206,444 issued to Harry M, Oliver on Apr. 27, 1993 there is disclosed a device for indicating the number of rounds left in a magazine. This involves a Z shaped slot on the side of the magazine and markings on the follower. Unlike the present invention, there is disclosed no contemplation of using the gasses from the breech to advance the cartridges.
Lastly, U.S. Pat. No. 5,218,163 issued to Gary P. Dabrowski on Jun. 8, 1993 discloses a pressure relief mechanism for a gas operated firearm. This includes a number of spherical valve elements seated about the gas cylinder to vent excess pressure in a forward direction. This is dissimilar from the instant invention as there is no teaching towards either a piston powered follower, nor of the unique ratcheting pin arrangement disclosed herein.
None of the above inventions and patents, taken either singly or in combination, is seen to describe the instant invention as claimed.